The effect of battery charge levels of Mobile phone on the amount of Electromagnetic waves emission.

Purpose: Over the past decades, mobile phone usage have increased dramatically. Extensive development and use of mobile telecommunication services has increased exposure to radio frequency electromagnetic waves (RF-EMW) in the daily lives of humans, and concerns about the harmful effects of mobile phones have also increased on human health. Therefore, this study aimed to investigate the effect of battery charge levels of the mobile phone on electromagnetic waves emission.
Methods: The mobile phone used in the current study was HTC One E9+ (0.181 W/kg SAR) with a non-removable battery model Li-Po 2800 mAh. The power density was measured with the mobile phone set to operate at the 2G mode by a SMP2 Portable Electromagnetic Field Monitoring System. Power density was measured in Calling mode (50 sec), Called mode (40 sec) and Talking mode (360 sec) at the battery charge levels of 1, 5, 10, 15, 20, 30, 50, 60, 70, 80 and 100%.
Results: In Calling mode, the maximum electromagnetic waves were determined when the mobile phone had 1% battery charge and also while it was being charged. Contrary to Calling mode, there is no statistically significant difference between the power density emitted in Called mode and Talking mode at the various battery charge levels. Power density was found to be highest in the Called mode (29.11 μw/cm ² ), and to be higher in the Talking mode (23.005 μw/cm ² ) than in the Calling mode (10.27 μw/cm ² ).
Conclusions: The data of the present study can be used to monitor the daily exposure of mobile phone users as well as to estimate exposure levels in the laboratory and non-laboratory studies. As long as a mobile phone that is in the standby mode remains within the geographic domain of the operator's service zone, the power density emitted from that phone will be virtually zero, and any background wave can be attributed to other sources.
Competing Interests: Conflict of interestThe authors declare no conflict of interest.